Pumping mechanism



P 2- D. J. DESCHAMPS 2,295,833

PUMPING MEGHANI SM Filed May is, 1941 gwuc/wtom fio're 47. Des aka/150s Patented Sept. 15, 1942 PUMPING MECHANISM Desire J. Deschamps, Rutherford, N. J., assignor to Bendix Aviation Corporation, South Bend,

Ind.,

a corporation of Delaware Application May 16, 1941, Serial No. 393,825

4 Claims.

This invention relates to pumps, and particularly to pumps of the high pressure class.

An object of the invention is to provide a pump having means inherent therein for discontinuing high pressure pumping upon attainment of a predetermined maximum pressure, and for resuming high pressure pumping upon subsequent reduction of pressure.

Another object is to provide a pump .having high pressure pumping elements in combination with lower pressure booster mechanism to .which the fluid to be pumped is first supplied,

and by which it is delivered to the higher pressure pumping elements which complete the pumping action.

Another object is to provide in a booster mechanism of the character indicated, and farther adapted to continue in operation even during those periods when the high pressure pumping elements are inactive; the booster serving during such periods, and at all times, as a circulatory system through which may circulate freely all that fluid which is unable to enter the high pressure chambers of the pump, by reason of the automatic cut-off action which limits the amount of work done in said high pressure chambers, and correspondingly limits the output of the pump to the predetermined maximum pressure, as heretofore noted.

These and other objects of the invention will become apparent from inspection of the following specification when read with reference to the accompanying drawing wherein is illustrated the preferred embodiment of the invention. It is to be expressly understood, however, that the drawing is for the purpose of illustration only, and is not designed as a definition of the limits of the invention, reference being had to the appended claims for this purpose.

In the drawing reference character nates a drive-shaft for a. wobble plate 6 adapted to drive a plurality of pistons 1 through the instrumentality of a corresponding number of slipper elements 8 and tappets 9. Each piston 'I has associated therewith a spring I I for the purpose of keeping tappets 9 and slippers 8 in contact with wobble plate 6 at all times and in every position of the pistons l. Asecond spring I2 is provided for each piston, said spring H being of greater strength than its opposing spring ll, so as to be able to over-power the latter.

In operation, the fluid enters at l6 and travels up through the booster pump I1, and from pump I! it flows into chamber I8. From chamber I8 it flows to pressure cut-01f valve chamber 5 desig- 2|, and through lateral ports 22 in valve 23, as shown, to chamber 24, and thence to the high pressure pump cylinders 26 through intake passages 21. Here it is pumped under pressure through check valves 29 to central chamber 3| and thence through high pressure outlet passages 32 and 33 to the point of use,'or to a storage tank. This delivered fluid also exerts pressure on fitted plunger 36, causing cut-off valve 23 to move against the resistance of spring 4|. When the maximum delivery pressure is reached, port 22 is cut-off and no more fluid can flow to chamber 24. Thus delivery of fluid is discontinued until such time as port 22 is opened due to a reduction in pressure on fitted plunger 36. When port 22 is closed the entire output of the booster pump I1 is of course by-passed around valve 43, and thence back into the pump IT.

The force of spring 4| is adjustable by manipulation of screw 44 and nut 46. Acorn nut 41 is used to protect parts 44 and 46, and to prevent leakage.

Pump I! may be of the gear type, the vane type, or any other desired type, but is shown as of an eccentric roller type in which the suction and discharge ports are in close proximity, wherefore the outlet passage 5| (to the chamber l8) lies adjacent the inlet passage l6, as shown; but of course there is no communication from one to the other, except through the interposed chambers of the booster l1.

What is claimed is:

1. In a device of the character described, the combination with a source of fluid of a series of fluid receiving chambers disposed in parallelism at equal distances from a common axis, booster means rotatable about said common axis for feeding fluid from said source to said chambers at a pressure greater than that at which the fluid is taken from said source, and means in said chambers for increasing the pressure of said fluid until a predetermined maximum pressure is attained.

2. In a device of the character described, the combination with a source of fluid of a series of fluid receiving chambers disposed in parallelism at equal distances from a common axis, booster means rotatable about said common axis for feeding fluid from said source to said chambers at a pressure greater than that at which the fluid is taken from said source, means in said chambers for increasing'the pressure of said fluid until a predetermined maximum pressure is attained, said means comprising a piston in each of said chambers, a wobble-plate for 2 actuating said pistons, and means for rotating said wobble-plate and booster about the common axis of said chambers.

3.'In a device of the character described, the combination with a source of fluid of a series of fluidv receiving chambers disposed in parallelism at equal distances from a common axis, booster means rotatable about said common axis for feeding fluid from said source to said chambers at a pressure greater than that at which the fluid is taken from said source, means in said chambers for increasing the pressure of said fluid until a predetermined maximum pressure is attained, and pressure-responsive means for discontinuing the feeding of fluid to said chambers upon attainment of said predetermined maximum pressure.

4. In a device of the character described, the

combination with a source of fluid of a series of fluid receiving chambers disposed in parallelism at equal distances from a common axis, booster means rotatable about said common axis for feeding fluid from said source to said chambers at a pressure greater than that at which the fluid is taken from said source, means in said chambers for increasing the pressure of said fluid until a predetermined maximum pressure is attained, and pressure-responsive means for discontinuing the feeding of fluid to said chambers upon attainment of said predetermined maximum pressure, said booster means thereafter operating as a fluid lay-passing means until there is a drop in pressure from the predetermined um.

DESIRE J. DESCHAMPS. 

